1、Designation: E1852 08E1852 13Standard Test Method forDetermination of Low Levels of Antimony in Carbon andLow-Alloy Steel by Graphite Furnace Atomic AbsorptionSpectrometry1This standard is issued under the fixed designation E1852; the number immediately following the designation indicates the year o
2、foriginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of antimony in c
3、arbon and low-alloy steel in the 0.0005 % 0.0005 % through0.010 % range.1.2 If this test method is used to test materials having contents less than 0.001 % antimony, users of different laboratories willexperience more than the usual 5 % risk that their results will differ by more than 50 % relative
4、error.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenc
5、ed Documents2.1 ASTM Standards:2E50 Practices forApparatus, Reagents, and Safety Considerations for ChemicalAnalysis of Metals, Ores, and Related MaterialsE135 Terminology Relating to Analytical Chemistry for Metals, Ores, and Related MaterialsE1184 Practice for Determination of Elements by Graphite
6、 Furnace Atomic Absorption SpectrometryE1601 Practice for Conducting an Interlaboratory Study to Evaluate the Performance of an Analytical MethodE1770 Practice for Optimization of Electrothermal Atomic Absorption Spectrometric EquipmentE1806 Practice for Sampling Steel and Iron for Determination of
7、Chemical Composition2.2 ISO Standards:3ISO 5725 Precision of Test MethodsDetermination of Repeatability and Reproducibility for a Standard Test Method byInter-Laboratory TestsISO 10698 SteelDetermination of Antimony ContentElectrothermal Atomic Absorption Spectrometric Method3. Terminology3.1 For de
8、finitions of terms used in this test method, refer to Terminology E135.4. Summary of Test Method4.1 The sample is dissolved in hydrochloric and nitric acids and diluted to volume. An appropriate aliquot is injected into thegraphite furnace atomizer of an atomic absorption spectrometer, which is equi
9、pped with a background correction. The sample isdried, pyrolized, and atomized. The absorbance of the radiation from the external light source is measured and compared to theabsorbance of samples of known position.NOTE 1In general, the deuterium correction system should be able to correct for the br
10、oad-band background absorbance up to 0.5 to 0.6 absorbanceunits. Zeeman systems should compensate for background levels as high as 1.0 to 1.5 absorbance units.1 This test method is under the jurisdiction of ASTM Committee E01 on Analytical Chemistry for Metals, Ores, and Related Materials and is the
11、 direct responsibility ofSubcommittee E01.01 on Iron, Steel, and Ferroalloys.Current edition approved March 1, 2008Nov. 15, 2013. Published March 2008January 2014. Originally approved in 1996. Last previous edition approved in 20012008as E1852 96 (2001).E1852 08. DOI: 10.1520/E1852-08.10.1520/E1852-
12、13.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from American National Standards Institute (AN
13、SI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depi
14、ct all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 194
15、28-2959. United States15. Significance and Use5.1 This test method is utilized for the determination of trace levels of antimony in carbon and low-alloy steel. It is assumedthat the procedure will be performed by trained analysts capable of performing common laboratory practices skillfully and safel
16、y.It is expected that the work will be performed in a properly equipped laboratory and proper waste disposal procedures will befollowed.6. Hazards6.1 For precautions to be observed in the use of certain reagents and equipment in this test method, refer to Practices E50.7. Apparatus7.1 Atomic Absorpt
17、ion Spectrometer with Graphite Furnace Atomizer, equipped with background corrector and appropriatesignal output device, such as video display screen, digital computer, printer or strip chart recorder, and autosampler. It isrecommended that the instrument meet the following performance requirements
18、after adjusting the instrument and optimizing thefurnace heating program as described in Practice E1770.7.1.1 The characteristic mass determined in accordance with Practice E1770 for antimony shall be less than 25 pg or within themanufacturers tolerance.7.1.2 The precision of the most concentrated b
19、lank addition solution shall not exceed 10 % of the mean absorbance of the samesolution. The precision of the least concentrated blank addition solution (excluding Solution B0) shall not exceed 4 % of the meanabsorbance of the most concentrated blank addition solution when determined in accordance w
20、ith Practice E1770.7.1.3 The limit of detection of antimony as described in Practice E1770 shall be less than 20 pg.7.1.4 Unless the instrument is provided with automatic curve correction circuitry, the graph linearity shall not be less than 0.95when determined in accordance with Practice E1770.7.2
21、Graphite Tubes, with pyrolytic coating and grooves for graphite platform, suitable for use with the graphite furnace unit.7.3 Graphite Platform, pyrolytic graphite, Lvov design, to fit graphite tubes specified in 6.27.2.7.4 LabwareTo prevent contamination of the sample(s), all beakers, lids, volumet
22、ric flasks, and funnels must be cleaned withhot HNO3 (1 + 1) before use.8. Reagents8.1 Purity and Concentration of ReagentsThe purity and concentration of common chemical reagents shall conform toPractices E50. It is important that antimony shall not exceed 0.01 g/mL in each of the reagents and 0.00
23、1 g/mL in the water.8.2 Antimony Stock Solution (1 mL = 1 mg Sb)Dissolve 0.1000 g 6 0.0001 g high-purity antimony (minimum 99.9 % Sb) in30 mLHCl + 5 mLHNO3 in a 100-mLbeaker. Boil gently to expel oxides of nitrogen. Cool and transfer the solution into a 100-mLvolumetric flask. Dilute to mark with HN
24、O3 (1 + 1) and mix. Store in polypropylene or high density polyethylene bottle.8.3 Antimony Standard Solution (1 mL = 10 g Sb)Transfer 1.0 mL of the antimony stock solution to a 100-mL volumetricflask, dilute to the mark with HNO3 (1 + 1), and mix. Prepare this solution immediately before use.9. Sam
25、pling and Sample Preparation9.1 Refer to Practice E1806 for devices and practices to sample liquid and solid steel.9.2 The sampling procedures shall not involve any steps or operations that can result in the loss of antimony in the sample.NOTE 2Arc melting of the sample or induction melting of the s
26、ample under vacuum may result in significant loss of several elements that have alow vapor pressure. Arc melting of the sample should be avoided and induction melting should be performed only in an at least partial inert atmosphere.9.3 The laboratory sample shall be cleaned by first washing in aceto
27、ne and air drying.9.4 If brazed alloy tools are used in the preparation of the sample, the sample shall be further cleaned by pickling in dilutednitric acid for a few minutes. The sample shall then be washed several times with water, then several times with acetone and airdried.10. Procedure10.1 Sam
28、ple MassFor samples containing between 0.0005 % and 0.0050 % antimony, the sample mass shall be 1.00 g,weighed to the nearest 0.1 mg. For samples containing between 0.0050 % and 0.010 % antimony, the sample shall be 0.25 gweighed to the nearest 0.1 mg.10.2 BlankSimultaneously with the sample, a blan
29、k test using the same quantities of all reagents shall be performed. Theantimony contents of the blank should be no greater than 10 ppb.ng/mL.10.3 Test SolutionTransfer the test portion in accordance with 9.110.1 into a 250-mLbeaker.Add 5 mLHCl and 50 mLHNO3.Cover the beaker with a watch glass, heat
30、 gently until the reaction ceases, and boil for 1 min to remove the oxides of nitrogen.E1852 13210.3.1 If sample contains tungsten or niobium, or both, transfer the test portion to a 100-mL beaker and add 1 mL H3PO4, 15mL HCl, and 5 mL HNO3. Cover beaker with watch glass, and heat gently until react
31、ion ceases. Evaporate the solution to 2 mLto 3 mL; then add 25 mL nitric acid. Boil for 1 min to remove oxides of nitrogen. Conduct a separate blank test correspondingto this procedure.10.3.2 Allow the solution, which may contain carbides, to cool. Add about 15 mL water, filter through medium textur
32、e filterpaper, and collect the filtrate in a 200-mL volumetric flask. Wash the filter paper several times with warm water and collect thewashings in the flask. Dilute to the mark with water and mix.10.4 Test Addition SolutionsTransfer separate 20.0-mL aliquotaliquots of the test solution into a seri
33、es of five 100-mLvolumetric flasks. Using a micropipette, inject the respective volumes of antimony standard solution indicated in Table 1. Diluteto the mark with water and mix. These solutions are referred to as S0, S1, S2, S3, and S4, respectively.10.5 Blank Addition SolutionsTransfer separate 20.
34、0-mLaliquots of the blank solution into a series of five 100-mLvolumetricflasks. Using a micropipette, add the respective volumes of antimony standard solution indicated in Table 2. Dilute to the markwith water and mix. These solutions are referred to as B0, B1, B2, B3, and B4, respectively.10.6 Opt
35、ical parameters used for the determination of antimony are given in Table 3.10.7 The atomic absorption spectrometer and the graphite furnace atomizer should be adjusted and optimized as described inPractices E1184 and E1770.NOTE 3The volume injected into the atomizer should be between 10 L and 50 L,
36、 depending on sensitivity, matrix interference, backgroundcorrection, and range of linearity. The volume 20 L is usually correct.10.8 Using the autosampler, inject the predetermined volume of the test solution and blank addition solutions in increasing orderinto the atomizer. Atomize each solution t
37、hree times. Record the three peak height readings.NOTE 4In most instances, the use of peak area integration is preferable.10.9 Check the instrument for memory effects, especially at high analyte levels, by running the blank firing program. Reset thebaseline to zero if necessary. Record the peak heig
38、ht reading for each determination (see Note 4).11. Plotting of Additions Graphs11.1 Calculate the average instrument readings for each of the blank addition solutions of 9.510.5 “B” against the mass ofantimony added, expressed in nanograms, in the blank addition solutions.11.2 Calculate the average
39、instrument readings for each of the test addition solutions of 9.510.4 “S” against the mass ofantimony added, expressed in nanograms, in the test addition solutions.NOTE 5In this test method, any nonspecific absorption effect is eliminated by the background correction of the instrument.Antimony may
40、be presentin the reagents. If antimony is present in the reagents, this plot may not pass through the origin.11.3 The standard additions graphs for the blank and the sample should be parallel.TABLE 1 Test Addition SolutionsName ofSolutionVolume ofAntimonyStandardSolutionAdded, LConcentrationof Antim
41、onyAdded in TestAdditionSolutions,ng/mLCorresponding Mass ofAntimony Added, ngVolumeInjected,10 LVolumeInjected,50 LS0 0 0 0.0 0.0S1 100 10 0.1 0.5S2 200 20 0.2 1.0S3 400 40 0.4 2.0S4 500 50 0.5 2.5TABLE 1 Test Addition SolutionsName ofSolutionVolume ofAntimonyStandardSolutionAdded, LConcentrationof
42、 AntimonyAdded in TestAdditionSolutions,ng/mLCorresponding Mass ofAntimony Added, ngVolumeInjected,10 LVolumeInjected,50 LS0 0 0 0.0 0.0S1 100 10 0.1 0.5S2 200 20 0.2 1.0S3 400 40 0.4 2.0S4 500 50 0.5 2.5E1852 13312. Calculation12.1 Most graphite furnace atomizers controlled by computers will calcul
43、ate the means, establish their own calibration curves,and calculate and display the results. If using instruments not having this capability, prepare the calibrations graphs and performthe calibration in accordance with 11.212.2 and 11.312.3.12.2 Determine the mass of antimony in the test and blank
44、addition solutions, mSb.1 and mSb.0, respectively, expressed innanograms, as the two intercepts on the mass axis by extrapolating the resulting straight lines in the two additions graphs (see10.111.1 and 10.211.2). The difference (mSb.1 mSb.0) gives the net mass of antimony, mSb, in the test solutio
45、n (Solution S1).12.2.1 The net mass of antimony, mSb, may also be calculated using the least-square-fit method applied to the two straight lines,the blank addition solutions (solutions “B”), and the test addition solutions (solutions “S”).The equation of the straight line relatingabsorbance to mass
46、is as follows:y 5a1bm (1)where:a andb = constants that correspond respectively to the intercept on the y axis and the slope of the straight line. Calculate b anda using the least-square-fit method as follows:b 5n(miyi 2(mi(yi#/n(mi 2 (mi! 2# (2)a 51/n! (yi 2b(mi!The intercept on the x axis with the
47、straight line of the slope b is (a/b):TABLE 2 Blank Addition SolutionsName ofSolutionVolume ofAntimonyStandardSolutionAdded, LConcentrationof AntimonyAdded in BlankAdditionSolutions,ng/mLCorresponding Mass ofAntimony Added, ngVolumeInjected,10 LVolumeInjected,50 LB0 0 0 0.0 0.0B1 100 10 0.1 0.5B2 20
48、0 20 0.2 1.0B3 400 40 0.4 2.0B4 500 50 0.5 2.5TABLE 2 Blank Addition SolutionsName ofSolutionVolume ofAntimonyStandardSolutionAdded, LConcentrationof AntimonyAdded in BlankAdditionSolutions,ng/mLCorresponding Mass ofAntimony Added, ngVolumeInjected,10 LVolumeInjected,50 LB0 0 0 0.0 0.0B1 100 10 0.1
49、0.5B2 200 20 0.2 1.0B3 400 40 0.4 2.0B4 500 50 0.5 2.5TABLE 3 Optical Parameters for Antimony DeterminationItem ParameterRadiation Source electrodeless discharge lamp (EDL) or hollow cathodelampLamp Current As recommended by lamp manufacturerSlit As recommended by instrument manufacturerWavelength 217.6 nmBackground Corrector yesTABLE 3 Optical Parameters for Antimony DeterminationItem ParameterRadiation Source electrodeless discharge lamp (EDL) or hollow cathodelampLamp Current As recommended by lamp manufacture
